Nobel winner to talk cats, computers and quantum physics

David Wineland in lab

Long before the days of internet cat videos, what was perhaps the original famous cat was born in the mind of Austrian physicist Erwin Schrödinger as an analogy to describe a foundational concept of quantum physics.

Schrödinger postulated a cat in a sealed box with a vial of poison that could be released by a random event such as a decaying radioactive particle. In this simplified view of quantum physics, the hypothetical cat is held in states of being alive and dead at the same time, until the box is opened to determine the cat’s state.

Now, 80 years later, Schrödinger’s cat may help describe a revolutionary technology future in the form of quantum computing. At 7 p.m. Tuesday, May 30, Nobel Prize-winning physicist David Wineland will give a free public lecture in Room 156, Straub Hall on his research into quantum phenomena and how it could lead to the most powerful computers ever created.

“It’s not every day we have the chance to hear a Nobel laureate explain the intricacies of quantum mechanics,” said Michael Raymer, a professor in the Department of Physics. “We’re fortunate to have him visiting the UO.”

Wineland’s talk, “Quantum Computers and Schrödinger’s Cat,” will delve into the strange world of quantum physics where all the rules of traditional physics seem to disappear — a world that exists at the atomic level and is especially difficult to study.

Wineland is the founder of a research group focused on ion storage at the National Institute of Standards and Technology in Boulder, Colorado. His work at the institute and as a member of the physics faculty of the University of Colorado at Boulder has led to advances in spectroscopy, atomic clocks and quantum information. Wineland’s research showed that ideas previously thought of as purely theoretical can be tested and measured in the laboratory.

Wineland will discuss the work that led to his 2012 Nobel Prize, which he won along with French physicist Serge Haroche for “groundbreaking experimental methods that enable measuring and manipulation of individual quantum systems.”

These newly measured phenomena at the single-atom level are intimately tied to the hot-button topic of quantum computing, which is based on the idea that as computer chips pack more data into smaller spaces, the materials that store individual pieces of data get smaller too. When these materials become single atoms, physicists say, everything starts behaving differently than in ordinary computers, and the physics principle of superposition of distinct states is needed to understand what happens.

While this poses significant challenges, scientists say it also opens the door to incredible opportunities in the form of quantum computers. Current computers store information in bits as either a 1 or 0, but a quantum computer would store information in quantum bits, or qubits, which can be a superposition of both 1 and 0, much as the hypothetical cat can be a superposition of alive and dead. Although such quantum trickery cannot be carried out for a real cat, Raymer says superpositions for qubits are quite real phenomena and lead to the power of quantum computing.

Physicists acknowledge this is a tricky concept to grasp since the idea that something can simultaneously be two different things seems impossible. Yet, scientists worldwide are now racing to harness the simultaneous nature of qubits to store and process vastly more data than can be stored as a humble 1 or 0.

“After such explanations, are you starting to feel like Schrödinger’s cat yourself, in a superposition of understanding and not understanding?” Raymer said. “Come to the lecture and David Wineland will help you understand.”

“Quantum Computers and Schrödinger’s Cat” is sponsored by the Department of Physics, the Center for Optical, Molecular and Quantum Science, and the Office of the Vice President for Research and Innovation. For more information, visit the UO’s Research and Innovation website.

—By Stephanie Nappa, Office for Research and Innovation